Valianto 1/8" (3mm) Air Micro Grinder, Pneumatic Pencil Die Grinder Polishing Engraver Tool Kit, 58000 RPM Free Speed Specification-----1/8" Collet-----1/4" Air Inlet-----2 CFM Avg. Air Consumption Working-----58000 RPM Free Speed-----90PSI Air Pressure-----High-speed pencil type grinder, can adapt to high speed precision machining Sophisticated interior design, easy use and durable. Speed Control-----Pencil Type Micro Air Die Grinder features a variable speed throttle control. Hose Protector-----Convenient hose with hose protector. Rear exhaust to prevent the chip flying anti-chip scattering and reduce noise. Occasion-----All kinds of metal precision grinding,Cutting plastic, stone, wood, etc., grinding, polishing, Clean jewelry, dies, rotors, backing plates, brake pads, cylinder heads, mounts and many other applications; suitable for hobby use